Machine tool



R. M. GAMBLE him/.30, 194s.

MACHINE TOOL Filed Feb. 18, 1946 I jaw/$7 J6 far/2% 'ov.30,1948 'R, 5 m; 2,454,916

MACHINE TOOL Filed Feb. 1.8, 1946 4 Sheets-Sheet a b5 ,Bnu W ZW I Nov. 30, 194 8.- R. M. GAMBLE MACHINE T0011 4 Sheets-Sheet 3 Filed Feb. 18, 1946 g QN R.- M. GAMBLE MAQHINE TQQL Nov. so, 1948.

Sheets-Sheet 4 'Filed Feb. 18, 1946 WM 6 h 6 Patented Nov. 30, 1948 "MACHINE root Ralph aGanibie, Springfiel'd, Wt, rassignomto limes ;& :Lamson Machine flomnany, fipring field, 'Vt. ,:-a-cor1g0ration of Mermont Application February 18, 1946; SerialflSio. 6458, 123

This invention relates to improvements in automatic machines 'for 'operating on wo'rk oieoe s, such for example as thread grinding machines. ,The zinvention is hereinafter described as -embodied ins machine in which work pieces are the machine in line vwith thespindle. :As .each work piece is carried from :the-lmagazineetoithe loading station, the preceding vwork piece on which the tooling operation has been-completed is simultaneously transferred vfrom the ;loading station to a-discharge-or receiving station,

Mechanism .is-also provided :for ,pushing the fresh work piece from :the transfer =.device=.tothe rchuckt where it is automatically-gripped spy the chuck, the chuckibeing operated by mechanism .in predetermined timed vrelation withltherm'ovee ments of the pushing. mechanism. At the end of the too-ling- .operation, the (finished piece isdischarged from the chuck to-the ,transfervmech- .anism by which it is transferred -.tothe.di-scharge station.

For a more completeunderstanding of the in.- vention, vreferenc may be vhad to :the following description of an embodiment thereof andrtoithe drawings, of which:

Figure 1 is a front elevation of the upperrportion of a grinding machine embodying the invention;

Figure 2 is a fragmentary section on Itherline .2-2 of Figure 1;

Figure 3 is a section on'the line .3-.3 of Figure Figure 4 is a section on thewline 4-4 of Figure 1; Figure 5 is a section on the linel5=5 .of'Figure Figure 6 is a detailed 'view of the discharge station shown in'Figure 3, a portion "beingFbroken away to show in section;

Figure '7 is'a sectionon the line 1- "of Figure figure-8 is a section on the line 8--8 'o i Figure 8 Glaims. ((31,.51- 215) 2 Figure 911s a1 seetiononathe dine 29-29 :dflliigure *Eigure It 0 :is a perspective zview of a a'cam :tdnum shocniiinrFigure 8;

Figure ill :is arsection '.on lithe lline ti-11 inf Eigurefi; t

Figure 1 .2 :ra izsectio-n on the line -t2-l2 of Eigurefi;

; "igune il-fi isa fragmentary fscctional "Vigil/V1011 a :tfori-zontal- :p'lane .of tithe (chuck and :spinclle, showing :the relation .theretomof the zram, work piecemnd carrier fingersgr and jgrinding wheel;

Figure 14 is a view-similar ito =Eijgure ;13 but showing .the v.iparts ;in :;a different pposition of operation;

:Figures 15 and. lGuMFQ-DljfiliG nriewstof. the parts shown in Figure le-,-eat,difierent st-ages iof opcra- :tion.

T e ie i d ma mbod n he let-6 m invention 18 preferably of the kind described and illustrated in U. 8. Patent .-No, 2,1312?! granted to Ralp Fl n r Janua 6 9: 9- upper portion .of such a -.machine .is illustrated im ie re lln qmeri e a ma m r bed .20 on which is rnountedka headstock Z2 and 'a il ock 14- ween t e ead iq k and the tailt sle tee a,.grim1ice w e t he sed in: the semi-cylindrical ,Wheelhead EB ii he v-wheel iszcarried frame-:30 which is angular-1y lad Justabl for.idiiterent lead anglesirnthe threads tozbe Cut wheel in theiworlr. ".Qn'the headstock an electricmotor n32, i is :mO'LlImCd -.to drive a am -tfl dwm isc ifi'b -which ths operations of the chucking :mechanism and the transfer. mechanismeare controlled timedirelatron ash r i e es ri ecl- 'B eadsteck 2:2 o a r es a atable s in e =5 ,0; W th whi h is a chuck .452: operatedwby an ejector rodr44, :the -.ejector;rodbeing :moved intone zdirectionnto; close the choc andiinz-tha othertdirection :to; open-the chuck :SlldifljfifltrthfiilWOlik.

The ttransfermechanismris illustrated infigure :3 faHdlGQmpIiSeS f1'rWO carrier .-'h eads iiflrand Q52 whichtane mounted respectively ion the (ends-10f .two. slide rrodsa'fi sand {:6 which :slideithrough hub imembersttneand -.62mespective1y ('fligurerBlgthese "hub members :being rnckahle ion a .zstub islrait (tit projecting horizontally from the headstock Q2. ,The carrier; head 55!] its :.:provihed twithra pair of fingers it whiehnmayrhe :of :spring. metal shaped fto grasp-:a work piece W,-itheiends of the fingers i-b'eing :fiare'd .:so that (they ean be 'push'ed against :a "Work piec'eeso :=as itosnap over its periphery-anti grip "the workpiece resiliently. ln like manner the earrier 'head -tz isprovided with a hair df spring fingers I2 adapted to grab and grip a work piece resiliently. The carrier head 50 is arranged to move through a path by which the fingers 70 transfer work pieces one by one from a supply station to a loading station in line with the chuck 42. The carrier head 52 is arrange for simultaneous movement with the carrier head 50, the former being made to follow a path from the loading station to a delivery station where the work pieces are stripped from the fingers I2. The carrier head 50 is actuated by an arm I4 which is pivoted at one end at I6 and at the other end to the carrier head 50. An arm I8 is pivoted at one end at 80 and at the other end to the carrier head 52 to actuate the latter. These arms are connected together for simultaneous movement by a connecting rod 82, the ends of which are connected to short arms 84 and 86 respectively which rock about axes I6 and 80 respectively and are secured to the arms I4 and I8. This linkage is actuated by rocking movement of the shaft 80 resulting from the rotation of the disc cam 36 (Figure 4) which is provided with a cam slot 88 in its face. In this slot rides a cam follower 90' on the end of a rock arm 92 which rocks about an axis-94. With the arm 92 looks another arm 96 having a gear segment 98 on the end thereof, the gear segment meshing with a corresponding gearsegment I mounted on the shaft 80. Thus the movements and positions of the carrier heads 50 and 52 are determined by the shape of the cam slot 88 as hereinafter described in more detail.

As indicated in Figures 3 and 9, the work pieces may be mounted in a circular magazine I02, transverse grooves I04 being provided in the periphery to hold individual work pieces in spaced relation. The magazine is housed in a casing I06 having an opening I08 through which the fingers I0 of the carrier head 50 enter to seize a work piece for transfer to the loading station. The grooves or notches I04, as indicated in Figure 9, are intersected by a deep circumferential groove I01 which provides clearance for the ends of the fingers when they enter the aperture I08 to sieze a work piece. In order to hold the magazine in successive positions in which one of the work pieces willbe in registry with the opening I08, a ratchet drum H0 is mounted on the magazine, a spring detent II2 being provided to enter the spaces between successive teeth of the ratchet so as to hold the magazine releasably in any one of its positions in which a groove I04 is in registry with the opening I08. With each operation of the carrier mechanism the magazine is indexed to bring the next successive work piece into registry with the opening I08. This is done by a pawl II 4 mounted on a plunger II6 which carries at its opposite end a dog II8 engaged by a pin I20 whenever the carrier mechanism operates. As shown in Figure 8, the pin I20 may be carried by the hub member 60 so that when the hub member is rocked, the pin will press against the dog II8 so as to move the pawl II4 to advance the magazine suinciently to bring the next successive work piece to the openin I08 where it can be seized by the fingers I0.

The carrier head 52 is employed to seize work pieces which have been tooled and are ready for discharge from the grinder. The fingers I2 transfer finished work pieces from the loading station to a dischargestation shown in Figures 6 and '7. At this station is a frame member I30 having a bore I32 therethrough. ,This bore is large enough to receive the fingers I2 with the work piece. A detent device is mounted in the member I30 and comprises a pair of plungers I34 projecting into the bore I32 and pressed in by springs I36. The plungers I34 are inclined with reference to the axis of the bore I32 so that when a work piece is thrust into the bore, it pushes the plungers back until the work piece passes, whereupon the plungers spring to their normal position and prevent the retraction of the work piece with the fingers I2 when the carrier head 52 starts on its reverse movement toward the loading station. When the work piece is stripped from the fingers I2, it falls down through a passage I40 in the member I30 and enters an inclined chute I42 down which it slides to the lower end I44 where it can be removed as desired or can be discharged into a suitable container (not shown).

When a work piece has been transferred from the magazine to the loading station in line with the chuck 42, it is thereupon pushed into the chuck so as to be gripped thereby. For this purpose an axially slidable ram I50 is mounted on the tail stock 24, this ram having at one end an abutment element I52 adapted to bear against the end of the work piece held in the loading position and to push a work piece into the chuck. At the other end of the ram a rod I54 projects axially and extends through an arm I56, the extremity of the rod I 54 having one or more nuts I58 threaded thereon. Between the ram I50 and the arm I56 is a .nut I60 which is spaced from the arm I56, a spring I62 being located on the rod between the nut I60 and the arm I56. As result of this arrangement, movement of the arm I 56 toward the right, as seen in Figure2, pulls the ram to the right with it. Movement of the arm I56 to the left pushes the ram resiliently through the compressed spring I62. Thus, if the ram encounters sufiicient resistance to its motion toward the left it can stop, any additional movement of the arm I56 in that direction being absorbed by the spring I62. The arm I 56 projects from a casting I64 which is slidably mounted on a tie rod I66, the tie rod extending the entire width of the machine and being axially movable. The casting I64 is sup ported partly by the tie rod I66 and partly by a short stub shaft I68 which extends through a wall of the main frame and is slidable therein.

Cam apparatus for causing a small amount of relative movement between the casting I64 and the tie rod I66 in a direction parallel to the axis 'of the spindle is provided as illustrated in Figures 2, 5, and 12. For this purpose, a collar I70 is fixed on the tie rod I 66. This collar has an arcuate extension I12 with the cam slot II4 therein. A cam follower I16 rides in slot II4, the cam follower I'I'6 being mounted on an arm I'I8 which projects radially from a sleeve I splined on a shaft I82. The arm I I8, in addition to the cam follower II6, also carries a cam block I84 which, as indicated in Figure 12, has parallel inclined faces. Against these faces are cam followers I 86 and I88 which are mounted on horns I00 and I82, these horns being integral with the casting I64. From Figures 2 and 12 it is evident that if the splined sleeve I80 is rocked, the resulting motion of the cam I84 will shift the casting I64 to the right or to the left according to the direction of the rocking movement of the sleeve I80. At the same time the engagement of the cam follower I I6 on the end of the arm I78 in the slot I14 will prevent relative axial movement saaeasre ihetweenthesleevevbflfi andthetierod Hi6. Hence, lif ithe :tie mod [65 r'is znotifree :to smove axially .at such time, .theccastingdfifl .will;move;in a direc- ;.tion parallel toithe -spindle .axisand this motion ;of-..the..casting USA' .will result in azcorresponding tmotionsof thezram {L51}. Itisithusevident that rocking movementofithesplined shaft m2 which carries :thesleeve its willzresult in:axial:move- .ment of' the ram 59, assuming that the 'tierod ilfifi/islheldzagainst axiaLmovement.

A similar structure is employed at the nether endcof themachineior thexaxial actuation .of the injector roda ld by :whichthe chuckz-Zisclosedio gripra workpiece .ortismpened toirelease awork :piece. .As shown in Figure 2, the :ejector rod 9 :passes :through and .is :secured to an .arm 1.94 which :projects ifrom .a casting 19B .slidable .on :theztiezrod J1EE. Fixed zonthe tie rodis acollar :I2981-having an zextensionilllllxwith a cam, slot 23.2

iinwvhichirides. a. cam..follower..2fl l onztheiend of :the arm 2&6 which projects-from a splinedzsleeire 2118 slidaloly mounted .on :a :splined shaft 5.211). Theshaftilflisaligned .with the shaft 582 but atheseztwoshaitsrock independently. The arm 1205 has a. cam ;block 2'l2 similar-to thecam block M4. On'ztheinclined parallel faces .of this cam .blockxride :a .--pair of :cam f'ollowers 2M and H which are mountedion hornsZlB and .220 of the masting I96. Thus, rocking movements of the gshaitllfl result in axialmovementsiof the ejector :rod d iiinone direction or the other, assuming :that'the tierod 166 is at such times held against .axialmovement. Fixed on the tierod Midis a ;:-collar .1222 .having anarm 22d projecting there- ;from with agroove in the end in .which is :re-

:a'tLsuch ,timeszno rocking movement is being'imwpartedto the shafts 21.9 and 182. It is thus'eviident :that by rocking .the shafts :28 fl and 482, axial movements of the ram 4'5!) and the ejector ;rod M relative to the spindle are produced for the purpose of pushing a work piece into the chuck and closing the chuck thereon. When "the work piece has been gripped toy the "chuck,

the-axial-movement of the spindle itself carries all the other associated members therewith so =thatthe' grip of "the chuck upon'the workis not -'disturbed. Axial'movemento'f the spindle' lllis obtained by a lead screw 2-38 which is splined toan extension of the spindle and which is in :ithreaded engagement with a fixed nut 2&0 mounted in a wall of the headstock. The lead screw 230 determines the pitch of the screw thread to be cut on the work piece. "This lead screw and the nut 2&0 can readily be'replaced 'When a-thread "of a different pit-ch istobe cut 'on thework. The spindle is rotated'by any suitable means such as a gear wheel'2'2 mounted -on-the spindle and meshing with an elongated pinion 2 M on a drive shaft 2%. .Asthe spindle 'isrotated,'the lead'screw 238 causes axial movement of the spindle at 'the proper rate to carry the work 'piece past the edge of the grinding "wheel'for the grinding of ascrew thread thereon.

Rocking movements of the individual splined .apparatuszsuchasithat; shown .in afiigures i1, 5, iii), andflsl. iReferring'ftotEigurer-5,:the-sshaft l.82..has :anrarmt 250 .proj-ecting:therefrom,;this-;arm being .connectedby 'a link3252 :to a parallel arm 12.54 rookableronva shortsshaftlzE 5.6. :Rockable with the arm .2154 :is razrocker 1280 which .is actuated lby a 'cpair -tof:plungerssififizand .263. The other ends of these plungers ride omcams mama .212 adjust- ;ablysmountedznn the drum 1341. As the drum 34 L'I'GVOIVBS, the'rockers 260 are actuated in suitable isequenceso :as to impart'rocking movements to the splinedishaits 2l.0: -and NM.

The icamscare so adjusted that the ram 15.0 pushes the work pie'celnto the chuckimmediatelysa'fter'theitransfer'fingers have brought the work :piece from the .magazine to the loading station. The ejector :rod 44 is atonce retracted 'to close therchuek-onthe work piece. The rotation: of 'th-e drum. '34 i'ssthereup on stopped and the rotationsof the spindle 'is commenced for the grinding operation. .At the conclusion of the grinding operation, the :spindle is stopped and the rotation of vtheucam drum is resumed for the purpose- 0f ejecting the work from .the chuck into thelcarrier fingers 12 which have been moved a into the loading station by :the rotation of the cam:disc;38.

Means for intermittent rotation of the drum 34 is shown inFigur-eza. .A xdrive shaft .280 is constantly driven=by ,themotor 32. Mounted on this drive shaft is a wheel 282 having a planetary pinion 2.34. mounted thereon .so that teeth of the pinionproject beyondthe periphery of the wheel 1232. TheseLteeth' mesh with the internal teeth of a ring agear $28.6 and. a'second ring gear 288, the numbers of teethiof these gears being different by .OIIGLOlStWO so that for each revolution of the shaft .ZBQthere isrelative movement between the ring gears-285.:and-28B and anangular distance represented by theone or two-teeth by whicnthey differ. 1Hen'ce,:if eitherring gear isheld against rotation, ?the:other rotates at arelatively slow speed. The ring gear 286 is mounted on the end'of atubular shaft Till] .to which is fixed the 10am drum 34 and athe cam disc :35. The ring gear :288 is mounted .onthe end oiia shaft 29.2 which is coaxialwith the T hollow shaft 290 and which vis freely rotatable unless held as hereinaiter described. -When the shaft 232 is allowed torrotate, the shaftiEQB-is held wmotienless by a clutch mechanism comprising a :sleeVeflM loosely mountedzon theshaft'292. This .sleeve has teeth at both ends for engagement alternate y with'corresponding'teeth on theihollow shaft 298 or with corresponding-teethon a .collar .296 which is splined .or keyedzon the shaft 282. The sleeve .294 is held against rotation so that whenitsiteeth are. meshed with those of theshaft 29G, itholds the shaft 29E! a ainst rotation while permitting the shaft 29:2 to rotate. When his meshed withrthe collarizflli. :it holds the. shaft 292 stationary while the shaft 2% is permitted to rotate. The's'leeve 2.94 is :held against rotation zbythezarmsi-of a fork. 2&8 whichrengage. inparallelzsegmental slots. in'its periphery. The. arms of :the forkfleiiproject f'roma hub portionsilll which is slidable on a stub shaftSilZ. The fork'Z-BB is .fixedby .a block 6M mounted on :a-rod 306. This rrod has .an arm .ttfi projecting therefrom, .asporthan of the :arm being .in the path of opposed .p1ungers .fiillandidtz which are actuated by sole- Thus. whenzthe solenoidsshift the fork 298 in one direotionltheshaftiZQfl is 'held against rotation so that there is then :no move- .mentof the. cam. drum edit .or'of the-cam disc :36.

v.sl'la'fts "'2 [D and 182 are controlled by suitable .75 ,gsslliftiof.theforktzflssinithe opposite dir eti chuck jaws.

sults in rotation of the cam drum and cam disc. This in turn resulting in actuation of the transfer mechanism and the chucking mechanism in timed relation to eject a work piece from the chuck, transfer such piece to the delivery station, introduce a fresh work piece to the loading station, push this work piece into the chuck, and close the chuck upon this work piece.

As illustrated in Figures 13 and 14, the chuck 42 is closed by engagement of a collar 320 on the ejector rod 44 with a shoulder 322 at the rear end of the chuck. Movement of the ejector rod 44 toward the right results in displacement of the chuck in the same direction to open the chuck and also results in the ejection of the work piece from the chuck to the waiting carrier fingers 12.

The machine operates as follows. At the conclusion of a grinding operation, the grinding wheel is withdrawn from the work by means not shown herein but described and illustrated in said Patent No. 2,187,227. The solenoid 310 is then energized to shift the clutch member 296 and thus to start the rotation of the cam drum 34 and disc 36. The latter acts through the cam follower 90 and the gear segments 98 and H10 to rock the shaft 83 so that the work-gripping fingers i and 12 move from intermediate positions of rest to the magazine openinglil and loading station respectively. At the magazine opening the fingers l0 grasp a fresh work piece to be operated on. At

the loading station, the fingers T2 snap on to the finished work piece which is still gripped by the While the fingers remain stationary in these positions, cams on the drum 34 operate to rock the shaft 2H3 (Figure 2) to shift the eJ'ector rod to the right, whereby the work piece W is released from the chuck and is pushed clear of the jaws (Figure 13) this work piece being embraced by the fingers 72. At the same time, another cam on the drum 34 acts to retract the ram I50 to the right. Continued rotation of the cam 34 and disc 38 causes the transfer mechanism to move to the position illustrated in Figure 3, the fingers I2 delivering the finished work piece to the discharge station while the fingers 70 bring a fresh work piece from the magazine to the loading station. Cams on the drum 34 then cause the shafts 182 and 2H (Figure 2) to rock, moving the ram ISO to the left to push the work piece into the chuck jaws and retracting the ejector rod to close the jaws on the work piece. The cam on the disc 36 then moves the fingers l0 and 12 to their idle positions. whereupon the solenoid 3 I S is energized to stop the rotation of the cam drum 34 and disc 35. The grinding wheel is brought up to engage the work piece and the grinding operation proceeds while the drum 34 is stopped. At the conclusion of the grinding operation, the wheel is withdrawn again, the rotation of the drum 34 and the disc 36'is resumed, and the next cycle begins.

I claim:

1. In a screw threading machine, a frame, a tool on said frame, a spindle rotatably mounted and axially movable onsaid frame, a chuck within said spindle, a ram axially movable on said frame in alignment with said spindle, cam actuated means for moving said ram to push a work piece to said chuck, automatic means for causing said chuck to grip a work piece pushed thereto, and means for axially moving said spindle and ram as a unit while the tool is in operative engagement with the work piece.

2. In a screw threading machine, a frame, a.

a tool on said frame, a spindle rotatably mounted and axially movable on said frame, a chuck within said spindle, a ram axially movable on said frame in alignment with said spindle, cam actuated means for moving said ram to push a work piece to said chuck, an ejector rod within said spindle movable in one direction to close said chuck and in the other direction to open the chuck and eject the work piece therein, cam actuated means for operating said ejector rod, and means for axially moving the spindle, ram and ejector rod as a unit for operative engagement of the tool with the work.

3. In a screw threading machine having a receiving station, a frame, a tool mounted on said frame, a rotatable and axially movable spindle mounted on said frame, a chuck within said spindle, means for transferring a work piece from said receiving station to a position in line with and adjacent to said spindle, automatic means for pushing a work piece from said position to said chuck, means for closing and opening said chuck to grip and release a work piece, means including a fixed nut on said frame and a lead screw fixed on said spindle and in threaded engagement with said nut to advance the spindle as it rotates for operative engagement of the tool with the work, and means for causing said chuck operating means and work pushing means to advance as a unit with the spindle.

4.. In a screw threading machine, a frame, a tool mounted on said frame, a spindle rotatable and axially movable on said frame, a chuck within said spindle, an axially movable member within said chuck to open and close the chuck, means connecting said spindle and said member for axial movement together as a unit, said means including elements relatively movable to cause axial movements of said member relative to said spindle to close and open said chuck.

5. In a screw threading machine, a frame, a tool on said frame, a spindle rotatable and axially movable on said frame, an axially slidable rod parallel to said spindle and connected thereto for axial movement in step therewith,-a chuck within said spindle, an ejector member coaxial with said spindle and movable relatively thereto to close and open the chuck, and cam means movable as a unit with said spindle and ejector member and rockable to cause relative movement between said spindle and ejector member, said cam means including an element slidable on said rod and secured to said ejector member, and a rockable member operatively connecting said rod and element and normally holding said rod and element against relative axial movement, said rockable member having cam surfaces arranged to cause relative axial movement of the element and rod when said rockable member is rocked.

6. In a screw threading machine, a frame, 'a tool on said frame, a spindle rotatable and axially movable on said frame, a chuck within said spindle, a ram aligned with said spindle and axially movable to push a work piece to said chuck, and a cam member axially movable as a unit with said spindle and said ram and rockable to cause relative axial movement between said spindle and said ram.

7. In a screw threading machine, a frame, a spindle rotatable and axially movable on said frame, a chuck in said spindle, a supply magazine spaced from said spindle, a discharge hopper, means for simultaneously transferring a work piece from said magazine to a loading position in line with said chuck and another work piece from said loading position to said hopper, means at said hopper for stripping from said transfer means Work pieces brought thereby to said hopper, a ram aligned with said spindle and movable relatively thereto to push a Work piece from the loading position to the chuck, means for actuating said ram, means for closing said chuck on a work piece and subsequently ejecting the Work piece from the chuck to the loading position, means for advancing said spindle and ram as a unit during the tooling of the work, and means for automatically operating all said means in timed sequence.

8. In an automatic machine for operating on a Work piece, a frame, a tool carried by said frame, a spindle rotatably mounted and axially movable on said frame, a chuck in said spindle, a ram aligned with said chuck and axially movable relatively to the chuck to press a Work piece REFERENCES CETED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,310,386 Bock July 15, 1919 1,862,042 Stevens June '7, 1932 

